The Guigala Tunnel Photo: VCG

The longest ultrahigh-altitude highway tunnel in the world, the Guigala Tunnel, in Southwest China's Xizang Autonomous Region, has been dug in both directions, marking the completion of a 7-year-construction period, China Media Group reported on Wednesday.

The average altitude of the Guigala Tunnel reaches 4,300 meters, with length of the left tunnel at 12.79 kilometers and 12.78 kilometers for the right.

Throughout the construction process, the drilling and blasting has encountered various challenges, including low oxygen and low temperature environment as well as complex geological conditions.

The tunnel is a vital component of the autonomous region's S5 line, a highway linking Lhasa city and Tesdang of Shannan in southwestern Xizang, which will greatly boost the economic development of Xizang region.

The completion of the Guigala Tunnel was the prerequisite of the formal operation of the S5 line which was scheduled to commence at the end of 2023. The highway will shorten the travel time between Lhasa and Shannan from previous three hours to one hour, and will fundamentally upgrade local transport connectivity, boost local tourism, agriculture and livestock sectors, according to the report.

The regional development and reform commission of Xizang vowed to deploy 191 key construction projects in the autonomous region in 2023, covering sectors of infrastructure, special industry development, ecological protection, border security and livelihood improvement backed with 143 billion yuan of investment, local media Xizang Daily reported on March 26.

A planned investment of 54.7 billion yuan will be used in the Linzhi-Ya'an section of the Sichuan-Xizang railway route, refurbishment of Lhasa Kongga International Airport and other construction projects involved in the infrastructure sector.

Xizang regional government conducted special campaign to secure the completion of multiple construction projects backed with an investment of 18 billion yuan, to help propel economic growth in the first quarter of 2023.

In the first quarter of 2023, Xizang's regional GDP hit 57.59 billion yuan, with the year-on-year growth rate of 8.2 percent ranking first among Chinese provinces, reflecting a positive and stable start for the region's economic recovery post-pandemic.